Reading "UI element states pseudo-classes" [1] I think that make sense:
1) to remove :checked pseudo class as it mimics exactly
input[type="radio"][checked] and input[type="checkbox"][checked] selectors
2) to remove :enabled pseudo class as it is enough to have :disabled
3) to remove:indeterminate as it describes behavior (redundant, btw) of
check/radio boxes only and on one particular platform.
Andrew Fedoniouk.
http://terrainformatica.com
[1] http://www.w3.org/TR/2001/CR-css3-selectors-20011113/#UIstates